I don't spend any money on days that i work, other than for transportation or groceries. am i being too frugal.?
No. Your just being sensible, and you'll likely thank yourself further down the line for not frittering money away on stuff you don't really need.
The number of days that you spend money is irrelevant. What matters is whether overall you are keeping within your income.
If you have a roof over your head that you pay to cool and heat and you're not suffering malnutrition from your food choices you're likely not being too frugal. Saving money is one of the most important things a human can do.
Not if it’s working for you.
Hard to say. Sounds like a good plan, but if you then overspend on the weekends, it's not really frugal.